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Chen H, Lu Z, Chen Y, Wu S, Zheng J, Qian Z. Advanced Oxidant Process with Fe(II)-Catalyzed Alkaline H 2O 2 Systems for Highly Efficient Concurrent Scavenging of NO and SO 2 in High Gravitational Fields. Ind Eng Chem Res 2022. [DOI: 10.1021/acs.iecr.2c03222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Hongyu Chen
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing100049, China
- Weiqiao-UCAS Research Institute, Huanghe 8th Road, Bingzhou256600, Shangdong, China
| | - Zhicheng Lu
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing100049, China
| | - Yang Chen
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing100049, China
| | - Shao Wu
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing100049, China
| | - Jianzhong Zheng
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing100049, China
| | - Zhi Qian
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing100049, China
- Weiqiao-UCAS Research Institute, Huanghe 8th Road, Bingzhou256600, Shangdong, China
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Yuan P, Ma H, Shen B, Ji Z. Abatement of NO/SO 2/Hg 0 from flue gas by advanced oxidation processes (AOPs): Tech-category, status quo and prospects. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 806:150958. [PMID: 34656565 DOI: 10.1016/j.scitotenv.2021.150958] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 09/27/2021] [Accepted: 10/09/2021] [Indexed: 06/13/2023]
Abstract
This review article provides a state-of-art insight into the removal of NO, SO2 and elemental mercury (Hg0) from flue gas by using advanced oxidation processes (AOPs) method. Firstly, the main flue gas purification strategies based on AOPs would be classified as gas-gas, gas-liquid and gas-solid systems preliminarily, and the primary chemistry/mechanism of the above homogeneous/heterogeneous reaction systems were presented as the oxidation of NO, SO2 and Hg0 by the oxidative free radicals (OH, O2 and SO4-etc.). Secondly, the research progress and reaction pathways for separately or simultaneously removing NO, SO2 and Hg0 from flue gas by AOPs has been reviewed elaborated and analyzed in more details. Notably, the wet/dry oxidation coupled with efficient absorption process would be a promising method of efficient removal of above gaseous pollutants. Subsequently, four types of assumed layout modes were described graphically. The application prospects of AOPs for the purification of flue gas from coal-fired boiler or industrial furnace were evaluated and found that the operation cost and utilization of oxidants must be reduced and improved respectively. Finally, the limitations in the current removal technologies based on AOPs are highlighted, meanwhile the future research directions are suggested, such as cut down the cost of oxidants and catalysts, improve the yield and valid utilization of highly reactive radicals and enhance the reactivity, resistance and stability of catalysts. Significantly, it is also envisaged that the review could enrich the knowledge repository to function as a scientific reference for the sustainable development of economical, effective and environment-friendly technologies for the abatement of a wide variety of emissions from flue gas, and further improve the feasibility and reliability of the strategies for moving from laboratory studies to large-scale development and industrial application.
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Affiliation(s)
- Peng Yuan
- School of Chemical Engineering & Technology, Hebei University of Technology, Tianjin 300130, PR China; Tianjin Key Laboratory of Clean Energy Utilization and Pollutants Control, School of Energy & Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China.
| | - Haofei Ma
- Tianjin Key Laboratory of Clean Energy Utilization and Pollutants Control, School of Energy & Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Boxiong Shen
- School of Chemical Engineering & Technology, Hebei University of Technology, Tianjin 300130, PR China; Tianjin Key Laboratory of Clean Energy Utilization and Pollutants Control, School of Energy & Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China.
| | - Zhiyong Ji
- School of Chemical Engineering & Technology, Hebei University of Technology, Tianjin 300130, PR China.
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Liu X, Zou Y, Geng R, Zhu T, Li B. Simultaneous Removal of SO 2 and NO x Using Steel Slag Slurry Combined with Ozone Oxidation. ACS OMEGA 2021; 6:28804-28812. [PMID: 34746573 PMCID: PMC8567348 DOI: 10.1021/acsomega.1c03572] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 09/28/2021] [Indexed: 05/12/2023]
Abstract
In this work, steel slag slurry was used in combination with O3 oxidation for the simultaneous removal of SO2 and NO x in a laboratory-scale wet flue gas desulfurization process. The effects of the oxidation temperature, steel slag concentration, initial SO2 concentration, and pH value on the desulfurization and denitrification efficiencies were studied. The results showed that the highest NO x removal efficiency occurred at an oxidation temperature of 90 °C. With an increase of the oxidation temperature above 90 °C, the denitrification efficiency decreased due to the decomposition of N2O5. The effect of the SO2 concentration on denitrification was complicated. When the concentration of SO2 was 500 ppm, generation of SO3 2- promoted the absorption of NO2. However, higher SO2 concentrations strengthened the competitive absorption of SO2 and NO x . In the pH range of 8.5-4.5, the denitrification efficiency was maintained at about 96%. The component analyses of the aqueous solution and the solid residue were conducted to investigate the compositions of the absorption products. The results showed that NO3 - and SO4 2- were the major anions in the aqueous solution. The nitrogen balance was analyzed to be 95.8%, clearly illustrating the migration and transformation path of nitrogen. In the solid residue, most alkaline substances were consumed, and the final products were mainly CaSO4 and FeO. Accordingly, the reaction mechanism of simultaneous desulfurization and denitrification using steel slag combined with ozone oxidation was proposed.
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Affiliation(s)
- Xiaolong Liu
- CAS
Key Laboratory of Green Process and Engineering, Institute of Process
Engineering, Innovation Academy for Green Manufacture, Chinese Academy of Sciences, Beijing 100190, China
| | - Yang Zou
- CAS
Key Laboratory of Green Process and Engineering, Institute of Process
Engineering, Innovation Academy for Green Manufacture, Chinese Academy of Sciences, Beijing 100190, China
| | - Ran Geng
- CAS
Key Laboratory of Green Process and Engineering, Institute of Process
Engineering, Innovation Academy for Green Manufacture, Chinese Academy of Sciences, Beijing 100190, China
- Faculty
of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Tingyu Zhu
- CAS
Key Laboratory of Green Process and Engineering, Institute of Process
Engineering, Innovation Academy for Green Manufacture, Chinese Academy of Sciences, Beijing 100190, China
- Center
for Excellence in Regional Atmospheric Environment, Institute of Urban
Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Bin Li
- Faculty
of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
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Liu Y, Liu L, Wang Y. A Critical Review on Removal of Gaseous Pollutants Using Sulfate Radical-based Advanced Oxidation Technologies. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:9691-9710. [PMID: 34191483 DOI: 10.1021/acs.est.1c01531] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Excessive emissions of gaseous pollutants such as SO2, NOx, heavy metals (Hg, As, etc.), H2S, VOCs, etc. have triggered a series of environmental pollution incidents. Sulfate radical (SO4•-)-based advanced oxidation technologies (AOTs) are one of the most promising gaseous pollutants removal technologies because they can not only produce active free radicals with strong oxidation ability to simultaneously degrade most of gaseous pollutants, but also their reaction processes are environmentally friendly. However, so far, the special review focusing on gaseous pollutants removal using SO4•--based AOTs is not reported. This review reports the latest advances in removal of gaseous pollutants (e.g., SO2, NOx, Hg, As, H2S, and VOCs) using SO4•--based AOTs. The performance, mechanism, active species identification and advantages/disadvantages of these removal technologies using SO4•--based AOTs are reviewed. The existing challenges and further research suggestions are also commented. Results show that SO4•--based AOTs possess good development potential in gaseous pollutant control field due to simple reagent transportation and storage, low product post-treatment requirements and strong degradation ability of refractory pollutants. Each SO4•--based AOT possesses its own advantages and disadvantages in terms of removal performance, cost, reliability, and product post-treatment. Low free radical yield, poor removal capacity, unclear removal mechanism/contribution of active species, unreliable technology and high cost are still the main problems in this field. The combined use of multiactivation technologies is one of the promising strategies to overcome these defects since it may make up for the shortcomings of independent technology. In order to improve free radical yield and pollutant removal capacity, enhancement of mass transfer and optimization design of reactor are critical issues. Comprehensive consideration of catalytic materials, removal chemistry, mass transfer and reactor is the promising route to solve these problems. In order to clarify removal mechanism, it is essential to select suitable free radical sacrificial agents, probes and spin trapping agents, which possess high selectivity for target specie, high solubility in water, and little effect on activity of catalyst itself and mass transfer/diffusion parameters. In order to further reduce investment and operating costs, it is necessary to carry out the related studies on simultaneous removal of more gaseous pollutants.
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Affiliation(s)
- Yangxian Liu
- School of Energy and Power Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Lei Liu
- School of Energy and Power Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Yan Wang
- School of Energy and Power Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China
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Li C, Shi J, Cao Q, Luo Y, Liang H, Du C, Gao Y, Shi J. Role of H +, HF, SO 42- and kaolin in fixing Hg of coal fire sponge. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 772:145510. [PMID: 33770854 DOI: 10.1016/j.scitotenv.2021.145510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 01/24/2021] [Accepted: 01/25/2021] [Indexed: 06/12/2023]
Abstract
Coal fire sponges (CFS) are common in coal-fire areas. Due to the enrichment of Hg in CFS, large amounts of Hg are released by CFS into the atmosphere via natural weathering or solar radiation. Therefore, CFS should be of concern in Hg pollution management and control globally. In addition, CFS changes the Hg cycle path by capturing Hg from coal fires that would have entered the atmosphere. In this study, the concentration, distribution, species, and enrichment mechanism of CFS Hg were investigated. The results showed that the Hg concentration in CFS ranged from 1008 to 35,310 ng/g, with an average of 8932 ng/g (CFS number, n = 153). The Hg concentration of CFS in different types of land was found to be significantly inhomogeneous. To determine the status of subterranean spontaneous combustion, the Hg concentration was added, which can improve the effect of coal-fire monitoring. Compared to the background area topsoil, CFS was enriched in Hg, acid, SO42-, and total fluoride. The Hg species in CFS was primarily HgSO4, followed by HgO. However, the primary Hg species in the surrounding topsoil were HgCl2 and HgO. By the simulation experiment, it was determined that hydrofluoric acid (HF) was beneficial to activate the stable species in the coal-fire areas. HgCl2, HgO, or Hg0 were ionized by acid liquor or HF, which can promote Hg migration and increase the adsorbed ratio; in the presence of SO42-, the primary Hg species was HgSO4. Ultimately, Hg was absorbed by clay minerals and organic matter. The high-efficiency activation of steady Hg species by the coal-fire HF should be studied further.
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Affiliation(s)
- Chunhui Li
- MOE Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China; State Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology, Beijing 100083, China.
| | - Jingxuan Shi
- MOE Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Qingyi Cao
- State Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology, Beijing 100083, China
| | - Yating Luo
- MOE Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Handong Liang
- State Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology, Beijing 100083, China.
| | - Chuan Du
- State Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology, Beijing 100083, China
| | - Yu Gao
- MOE Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Jiyan Shi
- MOE Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China.
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